There are many techniques currently used for enhanced recovery of oil. Examples of such techniques are listed in the diagram shown in FIG. 1. The techniques include water flooding, CO2 flooding and polymer flooding for light crude oil, and steam flooding and fire flooding for heavy crude oil. The techniques are usually implemented individually and most of the techniques require low viscosity oil. These techniques also have many negative impacts, as they present an adverse environmental impact and high greenhouse gas emission, require high supply and costs for water, gas and chemicals, carry a high fuel cost and also present permitting problems.
The use of horizontal drilling and hydraulic fracturing (also known as fracking) is the predominate technique currently used to improve oil and gas extraction. This method cracks the rock surrounding the production well creating paths for the flow of oil and gas, as shown for example in FIGS. 2a and 2b. Hydraulic fracturing is a well stimulation process used to maximize the extraction of underground resources, namely oil and gas. The hydraulic fracturing process requires the acquisition of large quantities of source water, construction of a well, stimulation of a well, and disposal of waste. Hydraulic fracturing involves the pressurized injection of fracturing fluids commonly made up of water and chemical additives, into a geologic formation. The pressure exceeds the rock strength and the fluid opens or enlarges fractures in the rock. As the formation is fractured, propping agents, such as sand or ceramic beads, are pumped into the fractures to keep them from closing as the pumping pressure is released. The fracturing fluids are then returned to the surface. Gas and oil will flow from pores and fractures in the rock into the production well for subsequent extraction. Wells used for hydraulic fracturing are drilled vertically and horizontally, or directionally. For example, FIG. 2a depicts the process including vertical and horizontal drilling. Wells may extend to depths greater than 10,000 feet or less than 1,000 feet, and horizontal sections of a well may extend many thousands of feet away from the production pad located on the surface. FIG. 2b shows, for example, an oil, gas or brine reservoir 51 with production wells 58 feeding into an oil, gas and brine separator 56. The oil 57 that is separated is transported and stored. The hot brine 53 that is separated is sent back into the reservoir for hot brine flooding 57.
Once the oil and gas surrounding these fractured rock paths become depleted, the flow dramatically diminishes. As indicated in FIG. 24, oil or gas production (line 24a) significantly falls off within 12 to 18 months. The severity of the depletion curve requires that many wells be drilled and fractured to keep production rates up.
It is an objective of the invention is to accomplish the following with respect to crude oil: rejuvenate depleted wells, improve the extraction rate for green fields, increase the oil reserves, improve the life of the oil fields, eliminate flaring gas, create energy to sustain an oil field without an electric grid or diesel generators, and improve the costs and profitability associated with oil recovery and optionally generate extra electricity to sell to electric users.